/* poppler-media.cc: glib interface to MediaRendition
 *
 * Copyright (C) 2010 Carlos Garcia Campos <carlosgc@gnome.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
 */

#include "config.h"

#include <cerrno>

#include <goo/gfile.h>

#include "poppler-media.h"
#include "poppler-private.h"

/**
 * SECTION: poppler-media
 * @short_description: Media
 * @title: PopplerMedia
 */

typedef struct _PopplerMediaClass PopplerMediaClass;

struct _PopplerMedia
{
    GObject parent_instance;

    gchar *filename;

    gchar *mime_type;
    Object stream;
};

struct _PopplerMediaClass
{
    GObjectClass parent_class;
};

G_DEFINE_TYPE(PopplerMedia, poppler_media, G_TYPE_OBJECT)

static void poppler_media_finalize(GObject *object)
{
    PopplerMedia *media = POPPLER_MEDIA(object);

    if (media->filename) {
        g_free(media->filename);
        media->filename = nullptr;
    }

    if (media->mime_type) {
        g_free(media->mime_type);
        media->mime_type = nullptr;
    }

    media->stream = Object();

    G_OBJECT_CLASS(poppler_media_parent_class)->finalize(object);
}

static void poppler_media_class_init(PopplerMediaClass *klass)
{
    GObjectClass *gobject_class = G_OBJECT_CLASS(klass);

    gobject_class->finalize = poppler_media_finalize;
}

static void poppler_media_init(PopplerMedia *media) { }

PopplerMedia *_poppler_media_new(const MediaRendition *poppler_media)
{
    PopplerMedia *media;

    g_assert(poppler_media != nullptr);

    media = POPPLER_MEDIA(g_object_new(POPPLER_TYPE_MEDIA, nullptr));

    if (poppler_media->getIsEmbedded()) {
        const GooString *mime_type;

        media->stream = poppler_media->getEmbbededStreamObject()->copy();
        mime_type = poppler_media->getContentType();
        if (mime_type)
            media->mime_type = g_strdup(mime_type->c_str());
    } else {
        media->filename = g_strdup(poppler_media->getFileName()->c_str());
    }

    return media;
}

/**
 * poppler_media_get_filename:
 * @poppler_media: a #PopplerMedia
 *
 * Returns the media clip filename, in case of non-embedded media. filename might be
 * a local relative or absolute path or a URI
 *
 * Return value: a filename, return value is owned by #PopplerMedia and should not be freed
 *
 * Since: 0.14
 */
const gchar *poppler_media_get_filename(PopplerMedia *poppler_media)
{
    g_return_val_if_fail(POPPLER_IS_MEDIA(poppler_media), NULL);
    g_return_val_if_fail(!poppler_media->stream.isStream(), NULL);

    return poppler_media->filename;
}

/**
 * poppler_media_is_embedded:
 * @poppler_media: a #PopplerMedia
 *
 * Whether the media clip is embedded in the PDF. If the result is %TRUE, the embedded stream
 * can be saved with poppler_media_save() or poppler_media_save_to_callback() function.
 * If the result is %FALSE, the media clip filename can be retrieved with
 * poppler_media_get_filename() function.
 *
 * Return value: %TRUE if media clip is embedded, %FALSE otherwise
 *
 * Since: 0.14
 */
gboolean poppler_media_is_embedded(PopplerMedia *poppler_media)
{
    g_return_val_if_fail(POPPLER_IS_MEDIA(poppler_media), FALSE);

    return poppler_media->stream.isStream();
}

/**
 * poppler_media_get_mime_type:
 * @poppler_media: a #PopplerMedia
 *
 * Returns the media clip mime-type
 *
 * Return value: the mime-type, return value is owned by #PopplerMedia and should not be freed
 *
 * Since: 0.14
 */
const gchar *poppler_media_get_mime_type(PopplerMedia *poppler_media)
{
    g_return_val_if_fail(POPPLER_IS_MEDIA(poppler_media), NULL);

    return poppler_media->mime_type;
}

static gboolean save_helper(const gchar *buf, gsize count, gpointer data, GError **error)
{
    FILE *f = (FILE *)data;
    gsize n;

    n = fwrite(buf, 1, count, f);
    if (n != count) {
        g_set_error(error, G_FILE_ERROR, g_file_error_from_errno(errno), "Error writing to media file: %s", g_strerror(errno));
        return FALSE;
    }

    return TRUE;
}

/**
 * poppler_media_save:
 * @poppler_media: a #PopplerMedia
 * @filename: name of file to save
 * @error: (allow-none): return location for error, or %NULL.
 *
 * Saves embedded stream of @poppler_media to a file indicated by @filename.
 * If @error is set, %FALSE will be returned.
 * Possible errors include those in the #G_FILE_ERROR domain
 * and whatever the save function generates.
 *
 * Return value: %TRUE, if the file successfully saved
 *
 * Since: 0.14
 */
gboolean poppler_media_save(PopplerMedia *poppler_media, const char *filename, GError **error)
{
    gboolean result;
    FILE *f;

    g_return_val_if_fail(POPPLER_IS_MEDIA(poppler_media), FALSE);
    g_return_val_if_fail(poppler_media->stream.isStream(), FALSE);

    f = openFile(filename, "wb");

    if (f == nullptr) {
        gchar *display_name = g_filename_display_name(filename);
        g_set_error(error, G_FILE_ERROR, g_file_error_from_errno(errno), "Failed to open '%s' for writing: %s", display_name, g_strerror(errno));
        g_free(display_name);
        return FALSE;
    }

    result = poppler_media_save_to_callback(poppler_media, save_helper, f, error);

    if (fclose(f) < 0) {
        gchar *display_name = g_filename_display_name(filename);
        g_set_error(error, G_FILE_ERROR, g_file_error_from_errno(errno), "Failed to close '%s', all data may not have been saved: %s", display_name, g_strerror(errno));
        g_free(display_name);
        return FALSE;
    }

    return result;
}

#define BUF_SIZE 1024

/**
 * poppler_media_save_to_callback:
 * @poppler_media: a #PopplerMedia
 * @save_func: (scope call): a function that is called to save each block of data that the save routine generates.
 * @user_data: user data to pass to the save function.
 * @error: (allow-none): return location for error, or %NULL.
 *
 * Saves embedded stream of @poppler_media by feeding the produced data to @save_func. Can be used
 * when you want to store the media clip stream to something other than a file, such as
 * an in-memory buffer or a socket. If @error is set, %FALSE will be
 * returned. Possible errors include those in the #G_FILE_ERROR domain and
 * whatever the save function generates.
 *
 * Return value: %TRUE, if the save successfully completed
 *
 * Since: 0.14
 */
gboolean poppler_media_save_to_callback(PopplerMedia *poppler_media, PopplerMediaSaveFunc save_func, gpointer user_data, GError **error)
{
    Stream *stream;
    gchar buf[BUF_SIZE];
    int i;
    gboolean eof_reached = FALSE;

    g_return_val_if_fail(POPPLER_IS_MEDIA(poppler_media), FALSE);
    g_return_val_if_fail(poppler_media->stream.isStream(), FALSE);

    stream = poppler_media->stream.getStream();
    stream->reset();

    do {
        int data;

        for (i = 0; i < BUF_SIZE; i++) {
            data = stream->getChar();
            if (data == EOF) {
                eof_reached = TRUE;
                break;
            }
            buf[i] = data;
        }

        if (i > 0) {
            if (!(save_func)(buf, i, user_data, error)) {
                stream->close();
                return FALSE;
            }
        }
    } while (!eof_reached);

    stream->close();

    return TRUE;
}
